Developing apparatus



Filed May 13, 1958 2 Sheets-Sheet 1 June 27, 1961 c. F. BRUNDAGE 2,989,912

DEVELOPING APPARATUS Filed May 15, 1958 2 Sheets-Sheet 2 INVENTOR.

CLINTON F. BRUNDAGE m My ATTORNEYS United States Patent 2,989,912 DEVELOPING APPARATUS Clinton F. Brundage, Mahwah, N.J., assignor, by m'esne assignments, to Minnesota Mining and Manufacturing Company, St. Paul, Minn., a corporation of Delaware Filed May 13, 1958, Ser. No. 734,969 Claims. (Cl. 95-89) This invention relates to apparatus for developing light-sensitized prints and more particularly for developing diazotype prints by means of gaseous or vaporous developers.

One object of the present invention is to provide a small, compact and efficient apparatus for developing diazotype prints in an ammonia vapor which is simple in construction and operation.

Another object of the present invention is to provide a small, compact and eflicient apparatus for receiving a single diazotype print and for causing a predetermined quantity of ammonium carbonate crystals to be evaporated into an ammonia vapor of suflicient concentration to develop the print.

A further object is to provide a developing apparatus for diazotype prints in which a predetermined quantity of ammonium carbonate crystals is simultaneously measured and dispensed to a source of heat within a chamber containing said print.

A still further object of the present invention is to provide novel means for simultaneously measuring and dispensing to a chamber containing a diazoprint a measured amount of ammonium carbonate crystals which upon being heated will generate ammonia vapors of sufiicient concentration to develop the print.

The above and further objects and novel ieatures of the present invention will more fully appear from the following detail description when the same is read in connection with the accompanying drawings. It is to be expressly understood, however, that the drawings are for the purpose of illustration only, and are not intended as a definition of the limits of the invention.

In the drawings, wherein like reference characters refer to like parts throughout the several views,

FIG. 1 is a vertical longitudinal sectional view of a diazotype developer embodying the present invention;

FIG. 2 is a top plan view of the developer taken on line 22 of FIG. 1, certain of the parts broken away for purposes of clearer illustration; and

FIG. 3 is a side elevation taken on line 3-3 of FIG. 2, certain of the parts having portions broken away for purposes of clearer illustration.

In the illustrated and described embodiment of the invention, there is set forth in the drawings an apparatus for developing diazotype prints which are mounted in apertures in record cards commonly employed in connection with known and existing tabulating and sorting systems and machines. The diazotype prints are made by the commercial process known as the Ozalid or ammonia process. One of the most serious objections to the use of the Ozalid or ammonia process for diazotype reproduction in office copy work is the necessity of using a gas chamber in which ammonia vapors can be liberated in sufiicient concentration and in a desired distribution to achieve the desired conversion of the dyestutf in a rapid manner. In the past, such gas chambers have embodied rather elaborate equipment for sealing the vapors from the outside atmosphere and for vaporizing the ammonia gas by heating some ammonium hydroxide solutions introduced into the chamber on to an evaporating pan. Operation of this type of equipment requires highly skilled labor and the high overhead makes the process impractical for the occasional production of copy in oflice work. Moreover, the handling of aqua ammonia "ice is undesirable because of the strong concentration of fumes which attack the person handling it. The novel invention herein described eliminates all of these previous objections and now makes it possible to develop by the ammonia process one diazotype print at a time in a small and compact apparatus suitable for use in an ofiice.

There is shown in FIG. 1 one form of apparatus for developing diazotype prints wherein numeral 10 designates a base which is supported by legs 11. A casing 12 or suitable configuration encases the apparatus and is secured to a base 10. Bolted to base 10 is a vertically extending rectangular shaped, airtight chamber and having at the upper end thereof a pair of sealing members 14 and 15 which are identical in construction and, consequently, only one such member will be described. Sealing member '14 comprises a plate 16 which extends the length of the chamber 13 and has one side thereof secured to one wall of said chamber and the other side bent downwardly toward but not extending to the center of said chamber at an angle of approximately 45 degrees to the wall of said chamber. A plate 17 extends the length of chamber 13 and parallel to plate 16 and has one side secured to the opposite wall of chamber 13 with the other side thereof bent downwardly toward but not extending to the center of said chamber at an angle of approximately 45 degrees to the wall of the chamber. Plates 16 and 17 extend downwardly and toward the center of chamber 13 but do not meet, thereby leaving an open area between their ends. Fixedly secured to the lower "surfaces of plates 16 and 17 are strips 18 and 19 made from rubber, felt or other suitable resilient material. Strips 18 and 19 extend the length of plates 16 and 17 and chamber 13, and are substantially wider than the downwardly depending portions of each plate. The upper surfaces on the outer unsecured edges of strips 18 and 19 firmly abut each other thereby forming a vertical downwardly depending resilient airtight seal portion. As a card having an aperture with a diazotype print 20 mounted therein is pressed downwardly into said contacting surfaces, strips 18 and 19 will resiliently yield sufliciently to permit the card to pass through while at the same time constantly pressing against the card surfaces to maintain a seal about that portion held therebetween. A V-shaped stop member 21 is mounted to each end wall of the chamber to provide a stop means for card A as it is inserted in the chamber. Stop mem bers 21 are positioned on the end walls of the chamber a sufiicient distance below seal 15 to allow the diazotype print 20 to be entirely inserted into chamber 13. A rectangular aperture in casing 12 is positioned in alignment with the top of chamber 13 to facilitate the insertion of cards A into said chamber. Mounted on base 10 and at the bottom of chamber 13 is an electric coil heater 22. In the embodiment illustrated, the heater 22 utilizes 12 volts, therefore a transformer 23 is mounted to base 10 for converting a volt supply to 12 volts. A delivery mechanism 24, hereinafter to be described, delivers a predetermined quantity of ammonium carbonate crystals to a chute 25 which extends through a side wall of chamber 13 and has a discharge end sitioned 'over the electric coil heater 22. The predetermined quantity of ammonium carbonate crystals deposited on coil 22 will, when heated, evaporate to form an ammonia vapor in chamber 13 of sufiicient concentration to develop the diazotype print inserted into the chamber. When it is desired to develop another diazotype print mounted on another card, the cycle is repeated by inserting a new card and eifecting another deposit of a predetermined quantity of ammonium carbonate crystals as above described.

The delivery mechanism 24 comprises a block 'mem-- r 3 her 26 bolted to the upper end of a vertical frame 27 which is secured at its lower end to base 10. Block 26 has a cylindrical chamber or bore 28 enclosed at each end by plates 29 and 30. An aperture 31 extends from the top surface of block 26 downwardly into the chamber 28 and aperture 32 extends from the bottom surface of block 26 into chamber 28. Rotatably secured through the center of chamber 28 is a shaft 33 having the ends thereof journalled in plates 29 and 30. Fixedly secured to shaft 33 and within chamber 28 is a hub 84 having a width equal to the width of chamber 28. A plurality of blades 35 are positioned in a spaced apart relation to each other about the periphery of hub 34 with one end of each blade embedded in hub 34 and extending radially outwardly therefrom with the outer end thereof in contact with the annular surface of chamber 28. Blade members 35 have a width the same as the width of chamber 28 and hub 34, thus there are formed a plurality of pie-shaped compartments 36 each of which is defined by a pair of spaced apart blades 35 at the sides thereof, a segment of the peripheral surface of hub 34 and a peripheral segment of cylindrical chamber 28 and the side plates 29 and 30. As shown in FIG. 2, the hub 34 and blades 35 are rotatable on shaft 33 Within the confines of stationary cylindrical chamber 28. An adapter plate 37 having an aperture 37 is mounted on the top of block 26 with the aperture 37 in register with aperture 31. A container 38 containing a supply of ammonium carbonate crystals is suitably secured to adapter plate 37. Thus, as hub 34 is rotated, each compartment 36 will be 'filled with ammonium carbonate crystals as it comes into register with aperture 31 and upon continued rotation (counterclockwise, as shown in FIG. 3) each filled compartment 36 will rotate until it comes into register with aperture 32. Blades 35 are preferably made of a resilient material, such as rubber, to avoid the possibility of the crystals creating a stoppage by a partial entry into aperture 31. Suitably secured to aperture 32 is the upper end of chute 25 so that as each filled compartment 36 comes in register with aperture 32 and the end of chute 25, the measured amount of ammonium carbonate crystals will fall downwardly through chute 25 and onto heater coil 22.

Hub 34 and compartments 36 are rotated in a step-bystep motion by the novel mechanism shown in FIGS. 1 and 3. The shaft 33 extends outwardly through plate 30 and frame 27 and has fixedly attached at its outer end thereof a disc member 39. A plurality of pins 40 axially extend through disc 39 and are positioned around the outer circumference of disc 39. Disc 39 and hub 34 are fixedly secured to shaft 33 and in such a relation to each other that each pin 40 is in horizontal alignment with the center of the outer peripheral edge of a compartment 36. Thus, the rotational movement of pin 40 effect a corresponding movement of compartments B6. A vertically extending U-shaped arm 45 having projecting parallel legs 43 and 44 is positioned in such a manner that the leg portions straddle the peripheral edge of disc 39 and are in contact with the ends of pins 40. The forward edge of each leg 43, 44 has a shoulder 46 formed therein and a concave area 47 formed just below each shoulder portion. The forward end of a lever 49 extends through an aperture 50 in the lower end of arm 45 and between legs 43, 44 and is pivotally secured to said legs by a pin 48. Lever 49 is pivotally connected at 52 to the frame 27. The normal position of arm 45 and lever 49 is shown in solid lines in FIG. 3. In order to retain arm 43 in a normally downward position and with the upper end and shoulder 46 thereof normally urged against a pin 40, there is provided a spring 53 having one end secured to the frame 27 and the other end secured to the lower rear corner of the arm. Upon the application of a downward pressure to the rear portion of lever 49, the forward end thereof and arm 45 pivotally connected thereto will move upwardly to the position shown in dotted lines in FIG. 3. It will be observed in FIG. 3 that as pin 40 is moved upwardly, the next succeeding pin 40 is rotated into the space previously occupied by that pin and fits into the concave space 47 on legs 43 and 44 without coming into contact with said legs. Upon release of the downward pressure on the rear portion of lever 49, spring 53 will pull arm 45 downwardly to the starting position. It will be noted, as shown in FIG. 3, that the length of slot 50 is greater than the width of lever 49. This provides a clearance space permitting the pivotal movement between lever 49 and arm 45. Moreover, this clearance space also permits the upper end of arm 45 to be pivotally moved away from the pins 40 and disc 39 by a pressure in excess of that exerted by spring 53. Thus, as arm 45 is pulled downwardly, the forward edges of legs 43 and 44 which form shoulder 46 will come into contact with the succeeding pin 40 and said contact will pivotally move the upper end of arm 45 away from the pin against the tension of spring 53. As soon as shoulders 46 are moved to a position below the pin 40, the spring 50 will move arm 45 toward the pin to the position as shown in solid lines in FIG. 3. Arm 45 and shoulder 46 are then in position for a repeat cycle. The rotational movement of each pin 40 is sufficient to eifect the rotational movement of compartments 36 and to move one compartment into register with the discharge aperture 32 and one compartment into register with the refill aperture 31.

A rectangular shaped aperture 54 is located in the lower portion of a wall of chamber 13 to enable the operator to observe the operation within said chamber. A glass plate 55 is held over aperture 54 by a frame 56 which is suitably secured to the wall of chamber 13.

In operation, a record card having a diazotype exposed print mounted in an aperture therein is inserted into chamber 13 such that the exposed print is fully inserted into the chamber through seals 14 and 15. The outer end of lever 49 is pushed downwardly which in turn causes arm 45 and shoulder portions 46 to be raised upwardly, thereby engaging and moving a pin 40 which in turn rotates disc 39. Rotation of disc 39 causes the radially spaced compartments 36 to be rotated in a step-by-step movement with each compartment sequentially rotated first into register with the filling aperture and then into register with a discharge aperture 32 and a delivery chute 25. The ammonium carbonate crystals fall downwardly in chute 25 and are deposited on a heated coil 22. The ammonium carbonate crystals upon exposure to heat will evaporate to (form ammonia vapors in chamber 1 3 of suflicient concentration to develop the diazotype print which has been inserted into the chamber. When another exposed diazotype print is desired to be developed the same procedure is repeated. It is readily seen that this invention provides a small, compact and efficient apparatus for developing diazotype prints by the ammonia process wherein all the previously known disadvantages of similar types of apparatus have been eliminated. Prints may be developed one at a time or in a series, depending upon-the.-.

particular needs of the user without requiring detailed and expensive starting and operating procedure which would make the occasional single print development uneconomical. While the particular embodiment described utilizes ammonium carbonate crystals for the yielding of ammonia vapors, it is to be understood that other ammonium salts which yield ammonia vapors when heated may be used. Moreover, two exposed cards can be placed back to back so that their exposed surfaces are directed away from each other and by inserting the same into the chamber both prints will be simultaneously developed. Furthermore, it has been found that the crystal form of ammonium carbonate is preferable to a powder form because the powder has a great aifinity for moisture which impedes its qualities to flow into the dispensing and measuring apparatus.

While the present invention is herein illustrated and described in connection with the record card having a diazotype exposed print mounted in an aperture therein, it is equally adapted to the development of a diazotype exposed print in a frame or a support of any kind. Moreover, the chamber may be efliciently operated with a single seal 14 instead of the disclosed double seal 14, 15. Various changes may be made in the design and arrangement of the parts of the illustrated embodiment without departing from the spirit and scope of the invention, as will now be clear to those skilled in the art. It is therefore to be expressly understood that the present invention is not limited to the particular embodiment thereof herein illustrated and described.

What is claimed is:

1. An apparatus for developing diazotype prints mounted in a record card, comprising an air-tight chamher for receiving the print portion of a record card, a scalable opening in said chamber whereby when at portion of the record card containing said print is inserted into said chamber a seal is elfected about that portion of the card retained in said opening, a source of heat in said chamber, means to simultaneously measure and feed to said heat source a predetermined quantity of developing material which upon being heated will yield a gas of suflicient concentration to develop said print.

2. An apparatus as set forth in claim 1 wherein the scalable opening comprises a plurality of seals.

3. An apparatus as set forth in claim 1, wherein said last-mentioned means comprises a plurality of measuring devices fixediy secured to and rotatable with a shaft, a filling station and a discharge station within operational range of said measuring devices, and means to cause a step-by-step rotation of said measuring devices whereby each measuring device is sequentially exposed first to said filling station and then to said discharge station.

4. An apparatus as set forth in claim 10, wherein said chambers are rotated in a vertical plane and said filling station is located at the highest point of rotation of the outer edge portions of said chambers and said discharge station is located at the lowest point of rotation of the outer edge portions of said chambers.

5. An apparatus for developing diazotype prints mounted in a record card, comprising an air-tight chamber, a scalable opening in said chamber whereby when that portion of the record card containing said print is inserted into said chamber a seal is efiected about that portion of the card retained in said opening, a source of heat in said chamber, means to simultaneously measure and feed to said heat source a predetermined quantity of crystals of an ammonium salt comprising a plurality of pie-shaped measuring chambers radially extending outtw ardly from and fixedly secured to a rotatable shaft whereby said chambers are rotatable with said shaft, a filling station and a discharge station positioned adjacent the path of movement of said chambers and substantially degrees from each other, and means to cause a step-by-step rotation of said chambers whereby one chamber is in register with the filling station and another chamber is simultaneously in register with the discharge station.

6. An apparatus for developing diazotype prints mounted in a record card comprising an air-tight chamber, a source of heat within said chamber, means to measure and feed to said heat source a predetermined quantity of developing material which upon being heated will yield a gas of sufiicient concentration to develop said print, a scalable opening in a wall of said chamber whereby the print portion of said card may be inserted into said chamber and a seal maintained about the record card, means to retain said print portion of a card freely suspended within said chamber and out of contact with said source of heat whereby said gas will develop said print.

7. An apparatus as defined in claim 6 wherein said card retaining means will retain two cards with the print portions back to back for simultaneous development thereof by said gas.

8. An apparatus as defined in claim 6 wherein said means to retain said print portion suspended Within said chamber comprises stop means for engaging the print end of said card to limit the forward movement thereof into said chamber.

9. An apparatus as set forth in claim 6 including means extending over said source of heat to shield the same from said card suspended within said chamber.

10. An apparatus for developing mounted diazotype prints comprising an air-tight chamber, a scalable opening in said chamber for receiving a mounted diazotype print into said chamber, a source of heat in said chamber, a plurality of measuring chambers radially extending outwardly from and fixedly secured to a rotatable shaft whereby said chambers are rotatable with said shaft, a filling station for storing a quantity of developing material and a discharge station positioned adjacent the path of movement of said chambers, means connecting said discharge station with said heat source, and means to cause a step-by-step rotation of said chambers to sequentially s-top each chamber first in register with the filling station and then in register with the discharge station whereby a measured amount of developing material is fed to said heat source which, upon being heated, will yield a gas of sufiicient concentration to develop said print.

References Cited in the file of this patent UNITED STATES PATENTS 

